While chip cards are becoming a mainstay at brick-and-mortar retail checkouts, gas pump payment technology lags behind.

Visa and Mastercard have given U.S. gas station owners until October of this year to upgrade pumps to accept EMV chip cards, rejecting a deadline extension request from the Merchant Advisory Group. Gas station operators who fail to meet the deadline will be held liable for fraudulent transactions.

But industry sources who spoke to Bank Innovation say station owners are saddled with elevated costs and certification requirements, along with technical implementation issues.

“Changing the point of sale [at gas pumps] so they can accept EMV involves a certain amount of cost and hassle because for merchants, payments are just the tail end of things and not their primary business,” said payments consultant David True. Estimates of the collective investment required from the industry to upgrade pumps range from $3.9 billion to $6 billion.

Joshua Smith, chief executive officer of Gas Pos, a vendor for point-of-sale systems, told Bloomberg that the industry is “massively underprepared” because of a lack of technicians available to carry out upgrades. The report cited a Conexxus study stating that 70% of U.S. convenience stores had not upgraded outside pumps to EMV technology.

See also: How FICO is using AI to fight payments fraud

Aside from cost, the post-upgrade certification process also presents a formidable obstacle for gas station owners.

“Once you change the hardware, there’s a process known as certification — this is also governed by the rules of the card networks,” True explained. “You can change your hardware, but it has to be certified before it actually works, and there’s a backlog.”

Meanwhile, the four- to six-month time frame required to implement tech upgrades, along with user experience challenges with EMV at gas pumps also stand in the way of compliance by the deadline, argued payments consultant Deborah Baxley.

“Those stations who have enabled EMV on their pumps have turned the capability off since the user experience is so poor; they want to wait until the entire industry shifts over,” she said.

Gas station owners should be prepared to address a “tsunami” of counterfeit claims should fraud liability shift their way, she added. “The high costs of converting the pump hardware is daunting to these small owners, and they may lack appreciation of the risks they’re facing. The industry needs to educate them on potential fraud losses they’ll be facing.”

Bank Innovation Ignite, which will take place March 2-3 in Seattle, is a must-attend industry event for professionals overseeing financial technologies, product experiences and services. This is an exclusive, invitation-only event for executives eager to learn about the latest innovations.